orang-utan

(also orang-outang / -u:5tAN; -E9tAN/, orang-outan) n large ape with long arms found in Borneo and Sumatra 猩猩（产於波罗州和苏门答腊）. =>illus at ape 见ape插图.

optimist, optimistic, optimistically, optimization, optimize, optimum, option, optional, optometrist, opulence, opulent, opus, or, or else, or rather, or so, oracle, oracular, oral, orally, orange, orange squash, orange-blossom, orange-coloured, orangeade, orate, oration, orator, oratorical, oratorio, oratory, orb, orbit, orbital, orch, orchard, orchestra, orchestra pit, orchestra stalls (US orchestra), orchestral,